In the beginning, portable cleaning machines had small centrifugal pumps putting out around 25 to 35 pounds of pressure, with a water output of somewhere between 1/2 gallon and 1 gallon per minute. These machines were capable of doing an acceptable job of cleaning carpets and upholstery, especially in the hands of a skilled, motivated technician.
But as we all know, time marches on. Today's portables have pressure pumps and vacuum systems that emulate the power of truck-mounted machines. The way in which they are constructed has also improved. When I first entered the carpet-cleaning business, most portables featured lightweight, plastic construction, in some cases Fiberglas. There were even some units, such as the Steamway 400 I started out with, in which there was actually some metal to go along with the plastic panels.
In the past 30 years the science of plastics has evolved considerably. Most of today's portables are manufactured using a rotation-molding process with much-improved materials. The new shapes that are possible with the rotation molding allow for many features to be built into a portable machine, as well as providing a surprisingly strong, lightweight housing. Today's plastic machines are light-years beyond their forefathers, and should not be prejudged on those early models.
Today's portables may have lightweight pumps with pressure capabilities of up to 500 psi, developed in part because of the "horsepower" race run by manufacturers of portable machines. At the same time, there are machines that function without a pressure pump at all, instead relying on a connection to the customer's hot water faucet.
The portable manufacturers have also developed vacuum configurations that allow airflow of 150 to 200 CFM or more using centrifugal vacuum motors. Multiple vacuum motors, which may be 2-stage or 3-stage in parallel (multiple vacs pulling through the same manifold) or in series (one behind the other), will give varying degrees of performance. Multiple vacs in series will provide the most lift, while multiple vacs in parallel will provide the most CFM.
Some machines are designed so that the operator can manipulate some valves and run the vacs in parallel or series as they wish. Regardless of the configuration, if centrifugal vacuums are being used, 50 feet to 100 feet of recovery hose is at up upper end of allowances. Another factor that must be addressed when discussing these newer high-pressure super vac units is power. Many of these multi-motor, high-pressure systems will require two or more power cords on separate circuits.
One other aspect of portable use is also changing (most, if not all, would say for the better) is the need for the "bucket brigade." For years, using a portable entailed a steady flow of buckets of water, both dirty and clean. Part of your production team spent some of their time carrying buckets of clean water to the machine and carrying buckets of dirty water to the disposal site. Obviously, these tasks added considerably to the amount of time required to complete the job at hand.
Now we are seeing more machines designed with some manner of pump-out system, either as part of the cleaning unit itself or as an attachment, and with water-fill systems that eliminate the need to "bucket" clean water to the machine.
There has been, and probably always will be, a long-standing debate on the merits of a truckmount vs. a portable. But no matter with which camp you side, the fact is a good technician can get acceptable results when cleaning carpets or upholstery with either type of machine. Another fact is that not all jobs are accessible with a truckmount. Case in point: I have a high-rise condominium community less than two miles from me that will not allow a truckmount on the property. If your work order says "Point Brittany," you are going to use a portable. I also work an island that is 22 miles long with condos stacked 20 stories high, many of which are simply not accessible with a truckmount.
The bottom line is that the machine you choose, whether truck-mounted or portable, is a tool, one that is no better than the technician operating it. I'll take a decades-old prototype operated by a skilled tech over the latest state-of-the-art unit in the hands of a chimp any day. Get classroom training to fully understand the jobs you will be performing and the equipment you will be performing them with. And always remember: get it clean and get it dry.
Until next month, see ya!